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ADS7861
ADS
786
1
AD
S78
61
SBAS110D – DECEMBER 1998 – REVISED AUGUST 2007
Dual, 500kSPS, 12-Bit, 2 + 2 Channel,
Simultaneous Sampling
ANALOG-TO-DIGITAL CONVERTER
FEATURES
DESCRIPTION
●
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●
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The ADS7861 is a dual, 12-bit, 500kSPS, Analog-to-Digital
(A/D) converter with four fully differential input channels
grouped into two pairs for high speed, simultaneous signal
acquisition. Inputs to the sample-and-hold amplifiers are fully
differential and are maintained differential to the input of the
A/D converter. This provides excellent common-mode rejection of 80dB at 50kHz which is important in high noise
environments.
4 INPUT CHANNELS
FULLY DIFFERENTIAL INPUTS
2µs TOTAL THROUGHPUT PER CHANNEL
NO MISSING CODES
1MHz EFFECTIVE SAMPLING RATE
LOW POWER: 40mW
SSI SERIAL INTERFACE
OPERATING TEMPERATURE RANGE:
–40°C to +125°C
The ADS7861 offers a high-speed, dual serial interface and
control inputs to minimize software overhead. The output data
for each channel is available as a 12-bit word. The ADS7861
is offered in both an SSOP-24 and a QFN-32 package and is
fully specified over the –40°C to +125°C operating range.
APPLICATIONS
● MOTOR CONTROL
● MULTI-AXIS POSITIONING SYSTEMS
● 3-PHASE POWER CONTROL
CH A0+
SAR
CH A0–
COMP
SHA
SERIAL DATA A
CDAC
CH A1+
SERIAL DATA B
CH A1–
M0
M1
REFIN
Serial
Interface
Internal
2.5V
Reference
REFOUT
A0
CLOCK
CS
CH B0+
CH B0–
RD
SHA
COMP
CDAC
BUSY
CONVST
CH B1+
CH B1–
SAR
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
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Copyright © 1998-2007, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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ELECTROSTATIC
DISCHARGE SENSITIVITY
ABSOLUTE MAXIMUM RATINGS(1)
Analog Inputs to AGND, Any Channel Input ........ –0.3V to (+VD + 0.3V)
REFIN ..................................................................... –0.3V to (+VD + 0.3V)
Digital Inputs to DGND .......................................... –0.3V to (+VD + 0.3V)
Ground Voltage Differences: AGND, DGND ................................... ±0.3V
+VD to AGND ......................... –0.3V to +6V
Power Dissipation .......................................................................... 325mW
Maximum Junction Temperature ................................................... +150°C
Operating Temperature Range ...................................... –40°C to +125°C
Storage Temperature Range ......................................... –65°C to +150°C
This integrated circuit can be damaged by ESD. Texas Instruments
recommends that all integrated circuits be handled with appropriate
precautions. Failure to observe proper handling and installation procedures can cause damage.
NOTE: (1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods may degrade
device reliability.
ESD damage can range from subtle performance degradation to
complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could
cause the device not to meet its published specifications.
PACKAGE/ORDERING INFORMATION
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see
the TI website at www.ti.com.
TRUTH TABLE
M0
M1
A0
TWO-CHANNEL/FOUR-CHANNEL OPERATION
DATA ON SERIAL OUTPUTS
CHANNELS CONVERTED
0
0
0
Two Channel
A and B
A0, B0
0
0
1
Two Channel
A and B
A1, B1
0
1
0
Two Channel
A Only
A0, B0
0
1
1
Two Channel
A Only
A1, B1
1
0
X
Four Channel
A and B
Sequential
1
1
X
Four Channel
A Only
Sequential
X = Don’t Care.
BASIC CIRCUIT CONFIGURATION
ADS7861
1
DGND
2
CH B1+
SERIAL DATA A 23
3
CH B1–
SERIAL DATA B 22
4
CH B0+
BUSY 21
5
CH B0–
CLOCK 20
Clock Input
6
CH A1+
CS 19
Chip Select
7
CH A1–
RD 18
Read Input
8
CH A0+
CONVST 17
9
CH A0–
A0 16
A0 Address Select
10 REFIN
M0 15
M0 Address Select
11 REFOUT
M1 14
M1 Address Select
12 AGND
2
+VD 24
+VA 13
BUSY Output
Conversion Start
+
10µF
+
+5V Analog Supply
0.1µF
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ADS7861
SBAS110D
ELECTRICAL CHARACTERISTICS
Over recommended operating free-air temperature range at TA = –40°C to +125°C, +VA + VD = +5V, VREF = internal +2.5V, fCLK = 8MHz, and fSAMPLE = 500kSPS,
unless otherwise noted.
ADS7861I, E
PARAMETER
CONDITIONS
MIN
TYP
RESOLUTION
MAX
MIN
TYP
12
ANALOG INPUT
Input Voltage Range-Bipolar
Input Capacitance
Input Leakage Current
SYSTEM PERFORMANCE
No Missing Codes
Integral Linearity
Integral Linearity Match
Differential Linearity
Bipolar Offset Error
Bipolar Offset Error Match
Positive Gain Error
Positive Gain Error Match
Negative Gain Error
Negative Gain Error Match
Common-Mode Rejection Ratio
VCENTER = Internal VREF at 2.5V
–VREF
✻
TA = –40°C to +85°C
TA = –40°C to +125°C
Referenced to REFIN
±0.15
Referenced to REFIN
±0.15
At DC
VIN = ±1.25VPP at 50kHz
80
80
120
0.5
±2
±1
±0.5
✻
±0.5
✻
✻
±3
±3.5
3
±0.75
2
±0.75
2
±0.10
±0.10
✻
✻
✻
✻
2
DIGITAL INPUT/OUTPUT
Logic Family
Logic Levels: VIH
VIL
VOH
VOL
External Clock, Optional
Data Format
–72
–71
TA = –40°C to +85°C
TA = –40°C to +125°C
TA = –40°C to +85°C
TA = –40°C to +125°C
V
pF
µA
±1
✻
±1
✻
✻
2
±0.50
1
±0.50
1
✻
✻
76
75
70
72
71
✻
–80
2.5
±25
50
2
0.005
80
2.5
0.05
5
2.525
✻
2.6
1
✻
3.0
–0.3
3.5
+VDD + 0.3
1
✻
✻
✻
✻
✻
✻
dB
dB
dB
dB
dB
dB
V
ppm/°C
µVPP
mA
mV/µA
dB
V
µA
pF
✻
0.4
0.2
8
Binary Two's Complement
✻
4.75
✻
5
5
5
25
25
✻
✻
✻
✻
✻
✻
✻
✻
✻
Bits
LSB
LSB
LSB
LSB
LSB
LSB
% of FSR
LSB
% of FSR
LSB
dB
dB
µVrms
LSB
µs
µs
kSPS
ns
ps
ps
MHz
–76
–75
CMOS
IIH = +5µA
IIL = +5µA
IOH = –0.5mA
IOL = –0.5mA
✻
✻
✻
✻
✻
3.5
100
50
40
1.2
Bits
✻
500
2.475
✻
✻
✻
1.625
0.375
VOLTAGE REFERENCE
Internal
Internal Drift
Internal Noise
Internal Source Current
Internal Load Rejection
Internal PSRR
External Voltage Range
Input Current
Input Capacitance
UNITS
✻
±0.75
0.5
±1
±0.5
±0.5
DYNAMIC CHARACTERISTICS (VIN = ±2.5VPP at 100kHz)
Total Harmonic Distortion
TA = –40°C to +85°C
TA = –40°C to +125°C
SINAD
Spurious Free Dynamic Range
TA = –40°C to +85°C
TA = –40°C to +125°C
Channel-to-Channel Isolation
MAX
✻
✻
12
SAMPLING DYNAMICS
Conversion Time per A/D
Acquisition Time
Throughput Rate
Aperture Delay
Aperture Delay Matching
Aperture Jitter
Small-Signal Bandwidth
POWER SUPPLY REQUIREMENTS
Power Supply Voltage, +V
Quiescent Current, +VA
+VREF
15
±1
Noise
Power Supply Rejection Ratio
Power Dissipation
ADS7861IB, EB
5.25
8
8.5
40
42.5
✻
✻
✻
✻
V
V
V
V
MHz
✻
✻
✻
✻
✻
V
mA
mA
mW
mW
✻
✻
✻
✻
✻
✻
✻ Specifications same as ADS7861I, ADS7861E.
ADS7861
SBAS110D
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3
PIN CONFIGURATIONS
CLOCK 20
CH B0–
6
CH A1+
CS 19
7
CH A1–
RD 18
+VD
NC(2)
SERIAL DATA A
25
1
24
SERIAL DATA B
CH B1−
2
23
BUSY
CH B0+
3
22
CLOCK
CH B0−
4
21
CS
CH A1+
5
20
RD
CH A1−
6
19
CONVST
CH A0+
7
18
A0
CH A0−
8
17
M0
ADS7861(1)
12 AGND
+VA 13
12
13
14
15
16
+VA
NC(2)
NC(2)
M1
M1 14
AGND
11 REFOUT
11
M0 15
10
10 REFIN
NC(2)
A0 16
CH A0–
REFOUT
9
CONVST 17
CH A0+
QFN
CH B1+
9
8
26
BUSY 21
DGND
CH B0+
27
4
28
SERIAL DATA B 22
NC(2)
CH B1–
29
3
NC(2)
SERIAL DATA A 23
30
CH B1+
NC(2)
2
5
+VD 24
31
DGND
NC(2)
1
Top View
32
SSOP
ADS7861
REFIN
Top View
NOTE: (1) The thermal pad is internally connected to the substrate.
This pad can be connected to the analog ground or left floating.
Keep the thermal pad separate from the digital ground, if possible.
(2) NC = Not Connected.
PIN DESCRIPTIONS
SSOP QFN
PIN
PIN
4
NAME
DESCRIPTION
Digital Ground. Connect directly to analog ground (pin 12).
1
28
DGND
2
1
CH B1+
Noninverting Input Channel B1
3
2
CH B1–
Inverting Input Channel B1
4
3
CH B0+
Noninverting Input Channel B0
5
4
CH B0–
Inverting Input Channel B0
6
5
CH A1+
Noninverting Input Channel A1
7
6
CH A1–
Inverting Input Channel A1
8
7
CH A0+
Noninverting Input Channel A0
9
8
CH A0–
Inverting Input Channel A0
10
9
REFIN
11
10
REFOUT
12
12
AGND
13
13
+VA
Analog Power Supply, +5VDC. Connect directly to digital power supply (pin 24). Decouple to analog ground with a 0.1µF ceramic capacitor
and a 10µF tantalum capacitor.
14
16
M1
Selects between the Serial Outputs. When M1 is LOW, both Serial Output A and Serial Output B are selected for data transfer. When M1
is HIGH, Serial output A is configured for both Channel A data and Channel B data; Serial Output B goes into tri-state (i.e., high impedance).
15
17
M0
Selects between two-channel and four-channel operation. When M0 is LOW, two-channel operation is selected and operates in
conjunction with A0. When A0 is HIGH, Channel A1 and Channel B1 are being converted. When A0 is LOW, Channel A0 and Channel
B0 are being converted. When M0 is HIGH, four-channel operation is selected. In this mode, all four channels are converted in sequence
starting with Channels A0 and B0, followed by Channels A1 and B1.
16
18
A0
A0 operates in conjunction with M0. With M0 LOW and A0 HIGH, Channel A1 and Channel B1 are converted. With M0 LOW and A0 LOW,
Channel A0 and Channel B0 are converted.
17
19
CONVST
Convert Start. When CONVST switches from LOW to HIGH, the device switches from the sample to hold mode, independent of the status
of the external clock.
18
20
RD
19
21
CS
20
22
CLOCK
An external CMOS-compatible clock can be applied to the CLOCK input to synchronize the conversion process to an external source.
The CLOCK pin controls the sampling rate by the equation: CLOCK = 16 • fSAMPLE.
21
23
BUSY
BUSY goes HIGH during a conversion and returns LOW after the third LSB has been transmitted on either the Serial A or Serial B output
pin.
22
24
SERIAL
DATA B
The Serial Output data word is comprised of channel information and 12 bits of data. In operation, data is valid on the falling edge of
DCLOCK for 16 edges after the rising edge of RD.
23
25
SERIAL
DATA A
The Serial Output data word is comprised of channel information and 12 bits of data. In operation, data is valid on the falling edge of
DCLOCK for 16 edges after the rising edge of RD. When M1 is HIGH, both Channel A data and Channel B data are available.
24
27
+VD
Reference Input
2.5V Reference Output
Analog Ground. Connect directly to digital ground (pin 1).
Synchronization Pulse for the Serial Output.
Chip Select. When LOW, the Serial Output A and Serial Output B outputs are active; when HIGH, the serial outputs are tri-stated.
Digital Power Supply, +5VDC. Connect directly to pin 13. Must be ≤ +VA.
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ADS7861
SBAS110D
TYPICAL CHARACTERISTICS
At TA = +25°C, +VA + VD = +5V, and VREF = internal +2.5V, fCLK = 8MHz, fSAMPLE = 500kSPS, unless otherwise noted.
FREQUENCY SPECTRUM
(4096 Point FFT; fIN = 199.9kHz, –0.5dB)
0
0
–20
–20
Amplitude (dB)
Amplitude (dB)
FREQUENCY SPECTRUM
(4096 Point FFT; fIN = 99.9kHz, –0.5dB)
–40
–60
–80
–100
–40
–60
–80
–100
–120
–120
0
62.5
125
187.5
250
0
62.5
125
Frequency (kHz)
SIGNAL-TO-NOISE RATIO and
SIGNAL-TO-(NOISE+DISTORTION)
vs INPUT FREQUENCY
0.7
0.6
74
SNR
Delta from +25°C (dB)
SNR and SINAD (dB)
250
CHANGE IN SIGNAL-TO-NOISE RATIO
AND SIGNAL-TO-(NOISE+DISTORTION)
vs TEMPERATURE
76
72
SINAD
70
68
66
0.5
0.4
0.3
0.2
SINAD
SNR
0.1
0
64
1k
10k
100k
–0.1
–40
1M
85
Temperature (°C)
CHANGE IN SPURIOUS FREE DYNAMIC RANGE
AND TOTAL HARMONIC DISTORTION
vs TEMPERATURE
CHANGE IN POSITIVE GAIN MATCH
vs TEMPERATURE
(Maximum Deviation for All Four Channels)
+1
6
0
5
–0.5
THD
4
–1
3
–1.5
2
–2
SFDR
1
–2.5
0
–3
–1
–3.5
–40
25
Temperature (°C)
ADS7861
85
0.6
Change in Positive Gain Match (LSB)
7
SBAS110D
25
Input Frequency (Hz)
THD Delta from +25°C (dB)
SFDR Delta from +25°C (dB)
187.5
Frequency (kHz)
0.5
0.4
0.3
0.2
0.1
0
–40
25
85
150
Temperature (°C)
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5
TYPICAL CHARACTERISTICS (Cont.)
At TA = +25°C, +VA + VD = +5V, and VREF = internal +2.5V, fCLK = 8MHz, fSAMPLE = 500kSPS, unless otherwise noted.
CHANGE IN REFERENCE VOLTAGE
vs TEMPERATURE
2.51
0.2
0.18
0.16
Change in Reference (V)
Change in Negative Gain Match (LSB)
CHANGE IN NEGATIVE GAIN MATCH
vs TEMPERATURE
(Maximum Deviation for All Four Channels)
0.14
0.12
0.1
0.08
0.06
0.04
2.505
2.5
2.495
2.49
0.02
0
–40
25
85
2.485
–40
150
CHANGE IN BIPOLAR ZERO
vs TEMPERATURE
150
CHANGE IN BPZ MATCH vs TEMPERATURE
Change in Bipolar Match (LSB)
Change in Bipolar Zero (LSB)
85
1
0.75
0.5
25
Temperature (°C)
Temperature (°C)
B Channel
0.25
0
–0.25
A Channel
–0.5
–0.75
–40
25
85
0.75
0.5
0.25
0
–40
150
25
85
150
Temperature (°C)
Temperature (°C)
INTEGRAL LINEARITY ERROR vs CODE
CHANGE IN CMRR vs TEMPERATURE
86
1
85
0.75
84
0.5
83
0.25
ILE (LSB)
Change in CMRR (dB)
Typical of All Four Channels
82
81
–0.25
80
–0.5
79
–0.75
78
–40
–5
25
Temperature (°C)
6
0
55
85
–1
800
000
7FF
Hex BTC Code
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ADS7861
SBAS110D
TYPICAL CHARACTERISTICS (Cont.)
At TA = +25°C, +VA + VD = +5V, and VREF = internal +2.5V, fCLK = 8MHz, fSAMPLE = 500kSPS, unless otherwise noted.
DIFFERENTIAL LINEARITY ERROR vs CODE
INTEGRAL LINEARITY ERROR vs TEMPERATURE
1
0.8
Typical of All Four Channels
0.7
0.5
0.6
Change in ILE (LSB)
0.75
DLE (LSB)
0.25
0
–0.25
–0.5
0.2
0
–0.2
Negative ILE
–0.6
–1
800
000
–0.8
–40
7FF
25
85
Hex BTC Code
Temperature (°C)
DIFFERENTIAL LINEARITY ERROR
vs TEMPERATURE
INTEGRAL LINEARITY ERROR MATCH
vs CODE CHANNEL A0/CHANNEL A1
(Same Converter, Different Channels)
0.8
150
0.25
Positive DLE
0.2
0.6
0.15
0.4
0.1
0.2
ILE (LSB)
DLE Error (LSB)
0.4
–0.4
–0.75
Positive ILE
0
–0.2
–0.4
Negative DLE
0.05
0
–0.05
–0.1
–0.15
–0.6
–0.8
–40
–0.2
25
85
150
INTEGRAL LINEARITY ERROR MATCH
vs CODE CHANNEL A0/CHANNEL B1
(Different Converter, Different Channels)
INTEGRAL LINEARITY ERROR MATCH
vs TEMPERATURE
Channel A0/Channel B0
(Different Converter, Different Channels)
0.46
Change in INL Match (LSB)
0.47
0.2
0.1
0.05
0
–0.05
–0.1
–0.15
000
Hex BTC Code
SBAS110D
0.45
0.44
0.43
0.42
0.41
0.40
0.39
–0.2
ADS7861
7FF
Hex BTC Code
0.25
–0.25
800
000
Temperature (°C)
0.15
ILE (LSB)
–0.25
800
7FF
0.38
–40
25
85
150
Temperature (°C)
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7
INTRODUCTION
The ADS7861 is a high-speed, low power, dual, 12-bit A/D
converter that operates from a single +5V supply. The input
channels are fully differential with a typical common-mode
rejection of 80dB. The part contains dual, 2µs successive
approximation ADCs, two differential sample-and-hold amplifiers, an internal +2.5V reference with REFIN and REFOUT
pins and a high-speed parallel interface. The ADS7861
requires an external clock. In order to achieve the maximum
throughput rate of 500kSPS, the master clock must be set at
8MHz. A minimum of 16 clock cycles are required for each
12-bit conversion.
There are four analog inputs that are grouped into two channels (A and B). Channel selection is controlled by the M0, M1
and A0 pins. Each channel has two inputs (A0 and A1 and B0
and B1) that can be sampled and converted simultaneously,
thus preserving the relative phase information of the signals on
both analog inputs. The part accepts an analog input voltage in
the range of –VREF to +VREF, centered around the internal
+2.5V reference. The part will also accept bipolar input ranges
when a level shift circuit is used at the front end (see Figure 7).
All conversions are initiated on the ADS7861 by bringing
the CONVST pin HIGH for a minimum of 15ns. CONVST
HIGH places both sample-and-hold amplifiers in the hold
state simultaneously and the conversion process is started on
both channels. The RD pin can be connected to CONVST to
simplify operation. Depending on the status of the M0, M1
and A0 pins, the ADS7861 will (a) operate in either twochannel or four-channel mode and (b) output data on both
the Serial A and Serial B output or both channels can be
transmitted on the A output only.
NOTE: See the Timing and Control section of this data sheet
for more information.
SAMPLE-AND-HOLD SECTION
The sample-and-hold amplifiers on the ADS7861 allow the
ADCs to accurately convert an input sine wave of full-scale
amplitude to 12-bit accuracy. The input bandwidth of the
sample-and-hold is greater than the Nyquist rate (Nyquist
equals one-half of the sampling rate) of the ADC even when
the ADC is operated at its maximum throughput rate of
500kSPS. The typical small-signal bandwidth of the sampleand-hold amplifiers is 40MHz.
Typical aperture delay time or the time it takes for the
ADS7861 to switch from the sample to the hold mode
following the CONVST pulse is 3.5ns. The average delta of
repeated aperture delay values is typically 50ps (also known
as aperture jitter). These specifications reflect the ability of
the ADS7861 to capture AC input signals accurately at the
exact same moment in time.
REFERENCE
Under normal operation, the REFOUT pin should be directly
connected to the REFIN pin to provide an internal +2.5V
reference to the ADS7861. The ADS7861 can operate,
however, with an external reference in the range of 1.2V to
2.6V for a corresponding full-scale range of 2.4V to 5.2V.
The internal reference of the ADS7861 is double-buffered.
If the internal reference is used to drive an external load, a
buffer is provided between the reference and the load applied to pin 2 (the internal reference can typically source
2mA of current load—capacitance should not exceed 100pF).
If an external reference is used, the second buffer provides
isolation between the external reference and the CDAC.
This buffer is also used to recharge all of the capacitors of
both CDACs during conversion.
ANALOG INPUT
The analog input is bipolar and fully differential. There are
two general methods of driving the analog input of the
ADS7861: single-ended or differential (see Figures 1 and 2).
When the input is single-ended, the –IN input is held at the
common-mode voltage. The +IN input swings around the
same common voltage and the peak-to-peak amplitude is the
(common-mode +VREF) and the (common-mode –VREF).
The value of VREF determines the range over which the
common-mode voltage may vary (see Figure 3).
When the input is differential, the amplitude of the input is the
difference between the +IN and –IN input, or (+IN) – (–IN).
The peak-to-peak amplitude of each input is ±1/2VREF around
this common voltage. However, since the inputs are 180° out
of phase, the peak-to-peak amplitude of the differential voltage is +VREF to –VREF. The value of VREF also determines the
range of the voltage that may be common to both inputs (see
Figure 4).
–VREF to +VREF
peak-to-peak
ADS7861
Common
Voltage
Single-Ended Input
VREF
peak-to-peak
Common
Voltage
ADS7861
VREF
peak-to-peak
Differential Input
FIGURE 1. Methods of Driving the ADS7861 Single-Ended
or Differential.
8
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ADS7861
SBAS110D
+IN
CM +VREF
+VREF
CM Voltage
–IN = CM Voltage
–VREF
t
CM –VREF
CM +1/2VREF
Single-Ended Inputs
+IN
+VREF
CM Voltage
–VREF
CM –1/2VREF
–IN
t
Differential Inputs
NOTES: Common-Mode Voltage (Differential Mode) =
(IN+) + (IN–)
Common-Mode Voltage (Single-Ended Mode) = IN–.
2
The maximum differential voltage between +IN and –IN of the ADS7861 is VREF. See Figures 3 and 4 for a further
explanation of the common voltage range for single-ended and differential inputs.
FIGURE 2. Using the ADS7861 in the Single-Ended and Differential Input Modes.
5
5
4.7
VCC = 5V
VCC = 5V
4.1
3
2.7
Single-Ended Input
2.3
2
1
0.9
0
3
Differential Input
2
1.0
1
0.3
0
–1
1.0
4.0
4
Common Voltage Range (V)
Common Voltage Range (V)
4
–1
1.2
1.5
2.0
2.5
2.6
3.0
VREF (V)
1.0
1.2
1.5
2.0
2.5
2.6
3.0
VREF (V)
FIGURE 3. Single-Ended Input: Common-Mode Voltage
Range vs VREF.
FIGURE 4. Differential Input: Common-Mode Voltage
Range vs VREF.
In each case, care should be taken to ensure that the output
impedance of the sources driving the +IN and –IN inputs are
matched. Otherwise, this may result in offset error, gain
error and linearity error which will change with both temperature and input voltage.
capacitance has been fully charged, there is no further input
current. The source of the analog input voltage must be able
to charge the input capacitance (15pF) to a 12-bit settling
level within 2 clock cycles. When the converter goes into the
hold mode, the input impedance is greater than 1GΩ.
The input current on the analog inputs depend on a number
of factors: sample rate, input voltage, and source impedance.
Essentially, the current into the ADS7861 charges the internal capacitor array during the sampling period. After this
Care must be taken regarding the absolute analog input
voltage. The +IN input should always remain within the
range of GND – 300mV to VDD + 0.3V.
ADS7861
SBAS110D
www.BDTIC.com/TI/
9
TRANSITION NOISE
Figure 5 shows a histogram plot for the ADS7861 following
8,000 conversions of a DC input. The DC input was set at
output code 2046. All but one of the conversions had an
output code result of 2046 (one of the conversions resulted
in an output of 2047). The histogram reveals the excellent
noise performance of the ADS7861.
DESCRIPTION
ANALOG INPUT
Full-Scale Input Span
–VREF to +VREF (1)
Least Significant
Bit (LSB)
(–VREF to +VREF
+Full Scale
Midscale
Midscale – 1 LSB
–Full Scale
BIPOLAR INPUTS
The differential inputs of the ADS7861 were designed to
accept bipolar inputs (–VREF and +VREF) around the internal
reference voltage (2.5V), which corresponds to a 0V to 5V
input range with a 2.5V reference. By using a simple op amp
circuit featuring a single amplifier and four external resistors, the ADS7861 can be configured to except bipolar
inputs. The conventional ±2.5V, ±5V, and ±10V input
ranges can be interfaced to the ADS7861 using the resistor
values shown in Figure 7.
8000
Number of Conversions
7000
6000
5000
)/4096 (2)
DIGITAL OUTPUT
BINARY TWO’S COMPLEMENT
BINARY CODE
HEX CODE
4.99878V
0111 1111 1111
7FF
2.5V
0000 0000 0000
000
2.49878V
1111 1111 1111
FFF
0V
1000 0000 0000
800
NOTES: (1) –VREF to +VREF around VREF. With a 2.5V reference, this corresponds to a 0V to 5V input span. (2) 1.22mV with a 2.5V reference.
TABLE I. Ideal Input Voltages and Output Codes.
TIMING AND CONTROL
The operation of the ADS7861 can be configured in four
different modes by using the address pins M0, M1 and A0.
The M0 pin selects between two- and four-channel operation
(in two-channel operation, the A0 pin selects between Channels 0 and 1; in four-channel operation the A0 pin is ignored
and the channels are switched automatically after each
conversion). The M1 pin selects between having serial data
transmitted simultaneously on both the Serial A data output
and the Serial B data output or having both channels output
data through the Serial A port. The A0 pin selects either
Channel 0 or Channel 1 (see Pin Descriptions and Serial
Output Truth Table for more information).
The next four sections will explain the four different modes
of operation.
4000
3000
2000
1000
0
2044
2045
2046
2047
2048
Code (decimal)
Mode I (M0 = 0, M1 = 0)
With the M0 and M1 pins both set to ‘0’, the ADS7861 will
operate in two-channel operation (the A0 pin must be used
to switch between Channels A and B). A conversion is
initiated by bringing CONVST HIGH for a minimum of
15ns. It is very important that CONVST be brought HIGH
a minimum of 10ns prior to a rising edge of the external
clock or 5ns after the rising edge. If CONVST is brought
FIGURE 5. Histogram of 8,000 Conversions of a DC Input.
R1
1.4V
4kΩ
OPA132
20kΩ
3kΩ
Bipolar Input
DATA
+IN
–IN
Test Point
ADS7861
100pF
CLOAD
R2
REFOUT
2.5V
VOH
DATA
VOL
tR
tF
BIPOLAR INPUT
R1
R2
±10V
±5V
±2.5V
1kΩ
2kΩ
4kΩ
5kΩ
10kΩ
20kΩ
Voltage Waveforms for DATA Rise and Fall Times tR, and tF.
FIGURE 6. Test Circuits for Timing Specifications.
10
FIGURE 7. Level Shift Circuit for Bipolar Input Ranges.
www.BDTIC.com/TI/
ADS7861
SBAS110D
HIGH within this window, it is then uncertain as to when the
ADS7861 will initiate conversion (see Figure 8 for a more
detailed description). Sixteen clock cycles are required to
perform a single conversion. Immediately following
CONVST switching to HIGH, the ADS7861 will switch
from the sample mode to the hold mode asynchronous to the
external clock. The BUSY output pin will then go HIGH and
remain HIGH for the duration of the conversion cycle. On
the falling edge of the first cycle of the external clock, the
ADS7861 will latch in the address for the next conversion
cycle depending on the status of the A0 pin (HIGH =
Channel 1, LOW = Channel 0). The address must be selected
15ns prior to the falling edge of cycle one of the external clock
and must remain ‘held’ for 15ns following the clock edge. For
maximum throughput time, the CONVST and RD pins should
be tied together. CS must be brought LOW to enable the two
serial outputs. Data will be valid on the falling edge of all 16
clock cycles per conversion. The first bit of data will be a
status flag for either Channel 0 or 1, the second bit will be a
second status flag for either Channel A or B. The subsequent
data will be MSB-first through the LSB, followed by two
zeros (see Table II and Figures 9 and 10).
tCKP
125ns
CLOCK
Cycle 1
Cycle 2
10ns
10ns
5ns
A
CONVST
5ns
B
C
NOTE: All CONVST commands which occur more than 10ns before the rising edge of cycle ‘1’ of the external clock
(Region ‘A’) will initiate a conversion on the rising edge of cycle ‘1’. All CONVST commands which occur 5ns after
the rising edge of cycle ‘1’ or 10ns before the rising edge of cycle 2 (Region ‘B’) will initiate a conversion on the
rising edge of cycle ‘2’. All CONVST commands which occur 5ns after the rising edge of cycle ‘2’ (Region ‘C’) will
initiate a conversion on the rising edge of the next clock period. The CONVST pin should never be switched from
LOW to HIGH in the region 10ns prior to the rising edge of the CLOCK and 5ns after the rising edge (gray areas). If
CONVST is toggled in this gray area, the conversion could begin on either the same rising edge of the CLOCK or
the following edge.
FIGURE 8. Conversion Mode.
TIMING SPECIFICATIONS
SYMBOL
tCONV
tACQ
tCKP
tCKL
tCKH
tF
tR
t1
t2
t3
t4
t5
t6
t7
t8
t9
t10
DESCRIPTION
MIN
Conversion Time
Acquisition Time
Clock Period
Clock LOW
Clock HIGH
DOUT Fall Time
DOUT Rise Time
CONVST HIGH
Address Setup Time
Address Hold Time
RD Setup Time
RD to CS Hold Time
CONVST LOW
RD LOW
CS to Data Valid
CLOCK to Data Valid Delay
Data Valid After CLOCK(1)
1.75
0.25
125
40
40
TYP
MAX
UNITS
5000
25
30
15
15
15
15
15
20
20
25
30
1
COMMENTS
µs
µs
ns
ns
ns
ns
ns
ns
ns
When TCKP = 125ns
When TCKP = 125ns
ns
ns
ns
ns
ns
ns
ns
Before falling edge of CLOCK
After falling edge of CLOCK
Address latched on falling edge of CLK cycle ‘2’
Maximum delay following rising edge of CLOCK
Time data is valid after second rising edge of CLOCK
NOTE: (1) ‘n – 1’ data will remain valid 1ns after rising edge of next CLOCK cycle.
CLOCK CYCLE
SERIAL DATA
1
2
CH0 OR CH1 CHA OR CHB
3
4
5
6
7
8
9
10
11
12
13
14
15
16
DB11
DB10
DB9
DB8
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
0
0
TABLE II. Serial Data Output Format.
ADS7861
SBAS110D
www.BDTIC.com/TI/
11
Mode II (M0 = 0, M1 = 1)
With M1 set to ‘1’, the ADS7861 will output data on the
Serial Data A pin only. All other pins function in the same
manner as Mode I except that the Serial Data B output will
tri-state (i.e., high impedance) after a conversion following
M1 going HIGH. Another difference in this mode involves
the CONVST pin. Since it takes 32 clock cycles to output
the results from both A/D converters (rather than 16 when
M1 = 0), the ADS7861 will take 4µs to complete a
conversion on both A/Ds (See Figure 11).
Mode III (M0 = 1, M1 = 0)
With M0 set to ‘1’, the ADS7861 will cycle through Channels 0 and 1 sequentially (the A0 pin is ignored). At the same
time, setting M1 to ‘0’ places both Serial Outputs, A and B,
in the active mode (See Figure 12).
Mode IV (M0 = 1, M1 = 1)
Similar to Mode II, Mode IV uses the Serial A output line to
transmit data exclusively. Following the first conversion
after M1 goes HIGH, the serial B output will go into tristate. See Figure 13. As in Mode II, the second CONVST
command is always ignored when M1 = 1.
READING DATA
In all four timing diagrams, the CONVST pin and the RD
pins are tied together. If so desired, the two lines can be
separated. Data on the Serial Output pins (A and B) will
become valid following the third rising SCLK edge following RD rising edge. Refer to Table II for data output format.
LAYOUT
For optimum performance, care should be taken with the
physical layout of the ADS7861 circuitry. This is particularly true if the CLOCK input is approaching the maximum
throughput rate.
12
The basic SAR architecture is sensitive to glitches or sudden
changes on the power supply, reference, ground connections
and digital inputs that occur just prior to latching the output
of the analog comparator. Thus, driving any single conversion for an n-bit SAR converter, there are n “windows” in
which large external transient voltages can affect the conversion result. Such glitches might originate from switching
power supplies, nearby digital logic or high power devices.
The degree of error in the digital output depends on the
reference voltage, layout, and the exact timing of the external event. Their error can change if the external event
changes in time with respect to the CLOCK input.
With this in mind, power to the ADS7861 should be clean
and well-bypassed. A 0.1µF ceramic bypass capacitor should
be placed as close to the device as possible. In addition, a
1µF to 10µF capacitor is recommended. If needed, an even
larger capacitor and a 5Ω or 10Ω series resistor may be used
to low pass filter a noisy supply. On average, the ADS7861
draws very little current from an external reference as the
reference voltage is internally buffered. However, glitches
from the conversion process appear at the VREF input and the
reference source must be able to handle this. Whether the
reference is internal or external, the VREF pin should be
bypassed with a 0.1µF capacitor. An additional larger capacitor may also be used, if desired. If the reference voltage
is external and originates from an op amp, make sure that it
can drive the bypass capacitor or capacitors without oscillation. No bypass capacitor is necessary when using the
internal reference (tie pin 10 directly to pin 11).
The GND pin should be connected to a clean ground point.
In many cases, this will be the ‘analog’ ground. Avoid
connections which are too near the grounding point of a
microcontroller or digital signal processor. If required, run a
ground trace directly from the converter to the power supply
entry point. The ideal layout will include an analog ground
plane dedicated to the converter and associated analog
circuitry.
www.BDTIC.com/TI/
ADS7861
SBAS110D
Conversion 1
Start of Conversion 2
tCKH
CLOCK
1
0
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
1
2
3
4
5
6
tCKL
t6
t1
CONVST
t2
t3
A0
t4
t5
t7
RD
CS
t9
t10
t8
SERIAL
DATA A
SERIAL
DATA B
0
0
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
D11
D10
D9
D8
0
0
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
D11
D10
D9
D8
BUSY
tCONV
tACQ
tCONV
FIGURE 9. Mode I with Timing Specifications.
1
16
CLOCK
A0
RD
Conversion of Ch0
Conversion of Ch1
CONVST
A0 LOW, Next Conversion: Ch0
A0 HIGH, Next Conversion: Ch1
RD Connected to CONVST
CS
CS HIGH, Outputs in Tri-State
SERIAL
DATA A
12-Bit Data of Chx
12-Bit Data of ChA1
SERIAL
DATA B
12-Bit Data of Chx
12-Bit Data of ChB1
BUSY
TIME 0
Conversion of Chx
1µs
Conversion of Ch0
Conversion of Ch1
2µs
3µs
4µs
5µs
6µs
Time (seconds)
FIGURE 10. Mode I, Timing Diagram for M0 = 0 and M1 = 0.
ADS7861
SBAS110D
www.BDTIC.com/TI/
13
1
16
CLOCK
Conversion of Chx
CONVST
M1 = 1 and 1st CONVST
Conversion
A0 HIGH
Next Conversion Ch1
A0
M1 = 1 and 2nd CONVST
No Conversion
M1 = 1 and 1st CONVST
Conversion
A0 LOW
Next Conversion Ch0
M1 = 1 and 2nd CONVST
No Conversion
A0 LOW
Next Conversion Ch0
M1
M1 HIGH
Only Serial Data A Used as Output Starting with 1st Conversion
RD
RD Connected with CONVST
CS LOW Output Active
CS
SERIAL
DATA A
12-Bit Data of ChAx
C
h
A
C
h
B
M1 = 1 and 1st CONVST
Data of ChA
M1 = 1 and 1st CONVST
Conversion
Conversion of Chx
BUSY
C
h M1 = 1 and 2nd CONVST
B
Data of ChB
M1 = 1 Serial Data B in Tri-state
12-Bit Data of ChBx
SERIAL
DATA B
C
h M1 = 1 and 1st CONVST
A
Data of ChA
M1 = 1 and 2nd CONVST
Data of ChB
M1 = 1 and 2nd CONVST
No Conversion
TIME 0
M1 = 1 and 1st CONVST
Conversion
M1 = 1 and 2nd CONVST
No Conversion
5µs
10µs
Time (seconds)
FIGURE 11. Mode II, Timing Diagram for M0 = 0 and M1 = 1.
1
16
CLOCK
4-Ch Operation and 1st Conversion Ch0
CONVST
M0 = 1 A0 Ignored
A0
M0
RD
4-Ch Operation and 2nd Conversion Ch1
M0 = 1, 4-Ch Operation Starts with Next Conversion
RD Connected with CONVST
CS
CS LOW, Output is Active
SERIAL
DATA A
12-Bit Data of ChAx
C
h
0
12-Bit Data of ChA0
C
h
1
12-Bit Data of ChA1
SERIAL
DATA B
12-Bit Data of ChBx
C
h
0
12-Bit Data of ChB0
C
h
1
12-Bit Data of ChB1
BUSY
TIME 0
1µs
2µs
3µs
4µs
5µs
6µs
Time (seconds)
www.BDTIC.com/TI/
FIGURE 12. Mode III, Timing Diagram for M0 = 1 and M1 = 0.
14
ADS7861
SBAS110D
1
16
CLOCK
Conversion of Chx
CONVST
M1 = 1 and 1st CONVST
Conversion
M1 = 1 and 2nd CONVST
No Conversion
M1 = 1 and 1st CONVST
Conversion
M1 = 1 and 2nd CONVST
No Conversion
M0 HIGH
4-Ch Operation Starts, A0 Ignored
A0
M0 = 1 and 1st Active CONVST
Ch0
M0 = 1 and 2nd Active CONVST
Ch1
M0
M0 HIGH
4-Ch Operation Starts
M1
M1 HIGH
Only Serial Data A Used as Output Starting with 1st Conversion
RD
RD Connected with CONVST
CS LOW Output Active
CS
SERIAL
DATA A
SERIAL
DATA B
BUSY
TIME 0
12-Bit Data of ChAx
CC
hh
0A
M1 = 1 and 1st CONVST
Data of ChA0
C C
h h M1 = 1 and 1st CONVST
1 A
Data of ChA1
CC
h h M1 = 1 and 2nd CONVST
1B
Data of ChB1
M1 = 1 Serial Data B in Tri-state
12-Bit Data of ChBx
Conversion of Chx
CC
h h M1 = 1 and 2nd CONVST
0 B
Data of ChB0
M1 = 1 and 1st CONVST
Conversion
M1 = 1 and 2nd CONVST
No Conversion
M1 = 1 and 1st CONVST
Conversion
5µs
M1 = 1 and 2nd CONVST
No Conversion
10µs
Time (seconds)
FIGURE 13. Mode IV, Timing Diagram for M0 = 1 and M1 = 1.
ADS7861
SBAS110D
www.BDTIC.com/TI/
15
Revision History
DATE REVISION PAGE
8/07
D
SECTION
DESCRIPTION
6
Pin Configuration
Added Note (1) to QFN package.
1
Entire Document
Changed Throughput Rate from 500kHz to 500kSPS throughout document.
1
Features
1
Description
2
Added Operating Temperature Range: –40°C to +125°C.
Changed Operating Temperature Range upper limit from +85°C to +125°C.
Absolute Maximum Ratings Changed Operating Temperature Range upper limit from +85°C to +125°C.
Changed top-of-page header condition to begin with:
"Over recommended operating free-air temperature range at..."
8/06
Changed "TMIN to TMAX" to "TA = –40°C to +125°C" in several locations.
C
3
Electrical Characteristics
Added TA = –40°C to +85°C to conditions for these parameters:
Bipolar Offset Error, Total Harmonic Distortion, Spurious-Free Dynamic
Range, Quiescent Current, and Power Dissipation.
Added new row for TA = –40°C to +125°C condition for these parameters:
Bipolar Offset Error, Total Harmonic Distortion, Spuriouse-Free Dynamic
Range, Quiescent Current, and Power Dissipation.
Moved "VIN = ±2.5VPP at 100kHz" from conditions of Dynamic Characteristics to
section header.
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
16
www.BDTIC.com/TI/
ADS7861
SBAS110D
PACKAGE OPTION ADDENDUM
www.ti.com
10-Aug-2007
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
ADS7861E
ACTIVE
SSOP/
QSOP
DBQ
24
ADS7861E/2K5
ACTIVE
SSOP/
QSOP
DBQ
ADS7861E/2K5G4
ACTIVE
SSOP/
QSOP
ADS7861EB
ACTIVE
ADS7861EB/2K5
56
Lead/Ball Finish
MSL Peak Temp (3)
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
24
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
DBQ
24
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
SSOP/
QSOP
DBQ
24
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ACTIVE
SSOP/
QSOP
DBQ
24
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861EB/2K5G4
ACTIVE
SSOP/
QSOP
DBQ
24
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861EBG4
ACTIVE
SSOP/
QSOP
DBQ
24
56
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861EG4
ACTIVE
SSOP/
QSOP
DBQ
24
56
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IBRHBR
ACTIVE
QFN
RHB
32
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IBRHBRG4
ACTIVE
QFN
RHB
32
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IBRHBT
ACTIVE
QFN
RHB
32
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IBRHBTG4
ACTIVE
QFN
RHB
32
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IRHBR
ACTIVE
QFN
RHB
32
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IRHBRG4
ACTIVE
QFN
RHB
32
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IRHBT
ACTIVE
QFN
RHB
32
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IRHBTG4
ACTIVE
QFN
RHB
32
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
56
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
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Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
10-Aug-2007
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
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Addendum-Page 2
www.BDTIC.com/TI/
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This package incorporates an exposed thermal pad that is designed to be attached directly to an external heatsink. The
thermal pad must be soldered directly to the printed circuit board (PCB). After soldering, the PCB can be used as a
heatsink. In addition, through the use of thermal vias, the thermal pad can be attached directly to the appropriate copper
plane shown in the electrical schematic for the device, or alternatively, can be attached to a special heatsink structure
designed into the PCB. This design optimizes the heat transfer from the integrated circuit (IC).
www.BDTIC.com/TI/
www.BDTIC.com/TI/
PACKAGE OPTION ADDENDUM
www.ti.com
10-Feb-2010
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
ADS7861E
ACTIVE
SSOP/
QSOP
DBQ
24
ADS7861E/2K5
ACTIVE
SSOP/
QSOP
DBQ
ADS7861E/2K5G4
ACTIVE
SSOP/
QSOP
ADS7861EB
ACTIVE
ADS7861EB/2K5
50
Lead/Ball Finish
MSL Peak Temp (3)
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
24
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
DBQ
24
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
SSOP/
QSOP
DBQ
24
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ACTIVE
SSOP/
QSOP
DBQ
24
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861EB/2K5G4
ACTIVE
SSOP/
QSOP
DBQ
24
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861EBG4
ACTIVE
SSOP/
QSOP
DBQ
24
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861EG4
ACTIVE
SSOP/
QSOP
DBQ
24
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IBRHBR
ACTIVE
QFN
RHB
32
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IBRHBRG4
ACTIVE
QFN
RHB
32
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IBRHBT
ACTIVE
QFN
RHB
32
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IBRHBTG4
ACTIVE
QFN
RHB
32
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IRHBR
ACTIVE
QFN
RHB
32
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IRHBRG4
ACTIVE
QFN
RHB
32
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IRHBT
ACTIVE
QFN
RHB
32
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
ADS7861IRHBTG4
ACTIVE
QFN
RHB
32
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
50
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
www.BDTIC.com/TI/
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
10-Feb-2010
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
www.BDTIC.com/TI/
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
11-Mar-2008
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
Diameter Width
(mm) W1 (mm)
A0 (mm)
B0 (mm)
K0 (mm)
P1
(mm)
W
Pin1
(mm) Quadrant
ADS7861E/2K5
SSOP/
QSOP
DBQ
24
2500
330.0
16.4
6.5
9.0
2.1
8.0
16.0
Q1
ADS7861EB/2K5
SSOP/
QSOP
DBQ
24
2500
330.0
16.4
6.5
9.0
2.1
8.0
16.0
Q1
ADS7861IBRHBR
QFN
RHB
32
3000
330.0
12.4
5.3
5.3
1.5
8.0
12.0
Q2
ADS7861IBRHBT
QFN
RHB
32
250
180.0
12.4
5.3
5.3
1.5
8.0
12.0
Q2
ADS7861IRHBR
QFN
RHB
32
3000
330.0
12.4
5.3
5.3
1.5
8.0
12.0
Q2
ADS7861IRHBT
QFN
RHB
32
250
180.0
12.4
5.3
5.3
1.5
8.0
12.0
Q2
www.BDTIC.com/TI/
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
11-Mar-2008
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
ADS7861E/2K5
SSOP/QSOP
DBQ
24
2500
346.0
346.0
33.0
ADS7861EB/2K5
SSOP/QSOP
DBQ
24
2500
346.0
346.0
33.0
ADS7861IBRHBR
QFN
RHB
32
3000
346.0
346.0
29.0
ADS7861IBRHBT
QFN
RHB
32
250
190.5
212.7
31.8
ADS7861IRHBR
QFN
RHB
32
3000
346.0
346.0
29.0
ADS7861IRHBT
QFN
RHB
32
250
190.5
212.7
31.8
www.BDTIC.com/TI/
Pack Materials-Page 2
www.BDTIC.com/TI/
www.BDTIC.com/TI/
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www.BDTIC.com/TI/
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